mars.tensor.random.uniform¶

mars.tensor.random.
uniform
(low=0.0, high=1.0, size=None, chunk_size=None, gpu=None, dtype=None)[source]¶ Draw samples from a uniform distribution.
Samples are uniformly distributed over the halfopen interval
[low, high)
(includes low, but excludes high). In other words, any value within the given interval is equally likely to be drawn by uniform. Parameters
low (float or array_like of floats, optional) – Lower boundary of the output interval. All values generated will be greater than or equal to low. The default value is 0.
high (float or array_like of floats) – Upper boundary of the output interval. All values generated will be less than high. The default value is 1.0.
size (int or tuple of ints, optional) – Output shape. If the given shape is, e.g.,
(m, n, k)
, thenm * n * k
samples are drawn. If size isNone
(default), a single value is returned iflow
andhigh
are both scalars. Otherwise,mt.broadcast(low, high).size
samples are drawn.chunk_size (int or tuple of int or tuple of ints, optional) – Desired chunk size on each dimension
gpu (bool, optional) – Allocate the tensor on GPU if True, False as default
dtype (datatype, optional) – Datatype of the returned tensor.
 Returns
out – Drawn samples from the parameterized uniform distribution.
 Return type
Tensor or scalar
See also
randint
Discrete uniform distribution, yielding integers.
random_integers
Discrete uniform distribution over the closed interval
[low, high]
.random_sample
Floats uniformly distributed over
[0, 1)
.random
Alias for random_sample.
rand
Convenience function that accepts dimensions as input, e.g.,
rand(2,2)
would generate a 2by2 array of floats, uniformly distributed over[0, 1)
.
Notes
The probability density function of the uniform distribution is
\[p(x) = \frac{1}{b  a}\]anywhere within the interval
[a, b)
, and zero elsewhere.When
high
==low
, values oflow
will be returned. Ifhigh
<low
, the results are officially undefined and may eventually raise an error, i.e. do not rely on this function to behave when passed arguments satisfying that inequality condition.Examples
Draw samples from the distribution:
>>> import mars.tensor as mt
>>> s = mt.random.uniform(1,0,1000)
All values are within the given interval:
>>> mt.all(s >= 1).execute() True >>> mt.all(s < 0).execute() True
Display the histogram of the samples, along with the probability density function:
>>> import matplotlib.pyplot as plt >>> count, bins, ignored = plt.hist(s.execute(), 15, normed=True) >>> plt.plot(bins, mt.ones_like(bins).execute(), linewidth=2, color='r') >>> plt.show()